Foundry system



Jan. 26, 1937. H. WURSTER 2,068,835

FOUNDRY SYSTEM Filed March 13, 1955 4 Sheets-Sheet l MOLD rRAMs-FnaCONVEYOR DEE] ASSEMBLM/ COOL //v JECf/O/V MOLD- MOLD MAk/A/q CONVEYOR LJ 3nnentor SAND RE ruAW HEA/R YA. WuRs 715R:

Y attorney FOUNDRY SYSTEM Filed March 15, 1935 4-Sheets-Sheet 2 I nEunentor fif/VR m. wups 75R (i ttorneg Jan. 26, 1937. H. A. WURSTERFOUNDRY SYSTEM Filed March 13, 1935 4 Sheets-Sheet 3 Snventor WURS 75/?TM (lt torneg HEA/QYA.

Jan. 26, 1937. A. WURSTER 2,068,335,

FOUNDRY SYSTEM a V attorney 45 wings, wherein:

Patented Jan. I 2 6, 1937 This invention relates broadly to founding andis particularly concerned with that phase of foundry work dealing withthe production of parts-castings of different types on a volume 5 basis,or the production of an entire assembly of castings going to make up acomplete machine or article regardless of whether or not volumeproduction is contemplated.

The'present invention may be considered in 10 the nature of animprovement over that disclosed in my prior Patent No. 1,911,542,granted May 30, 1933, and includes among its objects those noted in saidpatent, with alternate types of, and which for certain installations maybe considered 15 improved apparatus for carrying out such objects. Inthe present instance, th'e system is carried into and through thecasting department and the cycle completed from thee/making andassembling of the molds to the removal of the castings and return of thesand to' the conditioning plant and the return of the flasks to thepatterns or cope and drag plates at the start of the cycle.

A further important object of the present invention, in addition to thesaving of time and laher and reduction of production costs,is to lightenthe burden of the foundryman by eliminating heavy manual labor andrendering certain operations automatic so that he may devote more timeto constructive work and thereby produce better 30 castings generallyand be more content .and take a more active interest in his work.

Another object of the invention is to provide an improved foundingsystem capable of being carried out by apparatus which in general may beobtained in the open market and adapted to the improved system withoutchanging vital operatingparts-which have already demonstrated theirpracticability through actual usage, therea by eliminating costlyexperimentation and 40 changes in design which might otherwise vbenecessary. v

The oregoing, and other objects and advantages will become apparent inview of the follow- 1 g description taken in conjunction with the Figure1 is a plan view, more or less diagrammatic, of" apparatus constructedand coordinated ina manner such as to render it capable of carryto theillustration in Figure-1;

FigureB is a view in side elevation of Figure 2 taken'about on the line3-3 in the latter figure 55 and also including the sand-deliveryapparatT;

Figure 3a is an enlarged sectional view taken along the line 3-4 ofFigure 3; 2

Figure 4 is an enlarged sectional view taken. about on the line 4-4,Figure 2 and particularly showing one of the machines for the mold-mak-.5 ingiconveyor;

Figure 4m 'is a view in side elevation of Figure Figure 5 is a view inside elevation of a portion, of the mold-transfer conveyor;

Figures 6 and 7 are, respectively, views in side and end elevation ofautomatic weight-handling or mold-clamping machines forming part of theapparatus, said viewsbeing taken about on the lines 66 and 1-1, Figure1; and

Figure 8 is a -fragmentary view in side elevation of a'modifled type ofmold-making mecha:

nism.

.The term mold-making is meant to cover the making of molds for bothplain and cored .castings, or in other words, dry sand cores may be madein the same manner in which molds are made.

The entire lay-out is shown more or less diagrammatically in Figure l,and consists generally of a series of cordinated conveyors havingmounted thereon conveying and molding machines which carry the partsgoing to make up the molds. The molding sand is conveyed to the v flasksin a particularly advantageous manner directly from the sandconditioning plant, the sand being automatically leveled,'packed andthereafter returned to the conditioning plant.

The apparatus and method which I have provided includes three conveyorsystems, namely a mold making conveyor system, a mold transfer conveyorand a pouring conveyor system. The flrstof said systems comprisesgenerally a series of mechanisms which automatically and successivelyoperate to flll the mold flasks with loose 40 sand',.thereafter' jar andpack the loose sand around the pattern and raise the mold from thepattern. The second of said conveyor systems operates to transfer themolds from the first system'to the mold pouring conveyor system. Theintermediate system, that'is, the mold transfer system and the first andthird named systems overlap for a portion of their travel to permit theworkmen operating the foundry assembly to pick up the mold parts fromthe making conveyor and arrange them on the pouring conveyor. The

pouring-conveyor system includes a station carrying a series ofautomatically raised and lowered weights which. function to secure themold parts lnposition during the pouring. Subsequent to ,directiongenerally horizontal.

the pouring and the automatic removal of the weights referred to aconsiderable section of the pouring conveyor is utilized for cooling thecastings.

Referring to the drawings and the steps of my method in the sequence inwhich they are carried out the letters A, B and C adjacent the moldmaking conveyor indicated diagrammatically in Figure 1 indicatesstations where workmen arrange molding flasks and patterns upon a seriesof interconnected andages or machines which move continuously-in theoval orbit or path indicated. As the conveyor units with the mold flasksand patterns properly arranged thereon reach a point indicated at D,sand is discharged into the open top of the flasks. The molding sand ispreferably conditioned at a sand conditioning plant at 5 adjacent themold making conveyor and this plant may comprise an elevator G whichelevates sand from a pit to a feeder 1 from which it falls upon aconveyor means 8 which transports the sand to an aerating anddischarging assembly positioned above the flasks.

Since about 90% of the light casting work is known in the art as riddlework or work requiring a smooth finish, it is important that in acombined or automatic mold forming equipment such as I have providedthat the sand will be positioned about the patterns in a manner toproduce acceptable riddle work castings". Sand that is well conditionedby the known sand conditioning systems has a tendency to form lumps ofballs while being transported from the sand conditioning device to theflasks. Such undesirable sand exists whenever the sand is transported ona belt, trough, hopper or the like. Such lumpy sand even thoughotherwise well conditioned and aerated will not produce acceptableriddle work castings.

To overcome the objections incident to transporting conditioning sandfrom a sand conditioner to the pattern I have provided a novel sandagitating or discharging device at the end of the conveyor 3. Referringparticularly to Figures 3 and 3a the conveyor 8 is provided with anextension conveyor 8a which continues the movement of the sand from theconveyor 8 in a Sand plows l9 and we or analogous devices are placedabove the conveyor extension 8a and are so arranged as to scrape thesand off of the conveyor extension 3a and direct it into the open chutes9-911 and 91) arranged below the conveyor extension. The lower end ofthe chutes 9 and 9a are directed inwardly beneath the conveyor extensionso as to discharge sand at the outer edges of the relatively large orwide pattern arrangement whereas the lower end of the chute 9bterminates substantially in the center of the pattern arrangementpassing therebeneath and thus discharges sand into the central area ofthe patterns passing therebeneath. It will be appreciated that thisarrangement provides that in the event relatively small flasks or smallpattern arrangement are carried by the conveyor beneath the sanddischarge that the chute 9b alone may be employed to fill the moldingflask.

Whatever lumps or chunks of sand may have been formed during thetransporting of the sand from the conditioning plant 6 to the dischargeassembly are effectively broken up and completely aerated by theagitators or aerating devices I l disposed in the chutes 9-911 and 9b.As best shown in Figure 3a a motor Ha having a shaft lib is arrangedgenerally parallel to the conveyor track 3!.

veyor and transverse shafts 0 are provided with a driving connectiontherewith such as a bevel gear or the like and said shafts llc extendlaterally into the chutes 9, 9a and 9b. The agitators H secured to theshafts within the chutes are provided with plates which are curved andthus aid the force of gravity in directing the sand downwardly into theflask. It will be observed that this method of forcibly throwingaerated, perfectly conditioned sand against the patterns producesacceptable castings having a smooth finish and thus my methoddistinguishes over prior art methods wherein the sand is dropped orlowered into the mold flasks from a hopper.

The carriages or machines which travel steadily and continuously aboutthe mold making conveyor path are indicated generally at I? and comprisea frame 52b provided with flanged wheels 520. which normally rest uponthe con- A second set of flanged wheels .29 are provided to support thecarriage l2 during the jarring or jogging of the sand subsequent to thefilling of the flask. A short section of track 39 is provided adjacentthe sand discharging station and is formed with sloping ends to guidethe wheels 29 of the carriage I2 as they traverse this section of theconveyor path. This section of the conveyor path may be referred to asthe jarring station and the track 36 is rereferred to as an anvil trackinasmuch as the carriage i2 is provided with automatically operatedmechanism to forcibly raise and lower the pattern table l3 to jar thesand in the flask 1.

During the movements of the conveyor which jar or jog the sand intoposition around the pattern considerable settling and compacting of thesand takes place. The fact that the track 38 and wheels 29 are elevatedfrom the track 31 throughout this station prevents the transmission ofthe jarring or vibrating forces to the rest of the carriage or machinesH2 in the conveyor system. To effect the raising and lowering of theassembly which produces the jarring referred to a cylinder 520 ismounted at the underside of the carriage or machine i2 and carriestherein a piston lZd operatively connected to the pattern table IS. Aconduit i l leads from the cylinder I20 to an inlet chamber i'la whichis connected to a common flexible conduit l7 connecting all of thecarriages or machines 9 2. The conduit i7 is connected as at H! to aflexible lead-in conduit l8 arranged at the center of the mold makingconveyor systern.

As shown in Figures 2 and 3 a hose reel or the like 29 is mounted at acentral point within the conveyor orbit and a flexible conduit it?carried thereby leads to a conduit header fitting l9 which is carried bythe series of mold units on the conveyor, The reel attached end of theconduit is terminates at the rotational center of the reel 20 as isusual in such constructions.

Since the specific reel structure is but an element in the combinationof my invention any suitable reel structure may be employed at thispoint and preferably reel structures carrying flexible conduits such asthose disclosed in the patents to Ludwig No. 1,881,764 and Lea, No.1,908,852 are employed to conduct the fluid pressure from the centralpoint of the conveyor path to the header fitting l9 carried by the moldunits. As will be observed by reference to the Lea and Ludwig patentsand as is conventional in reel constructions of this type coil springsare arranged to tension the flexible conduit intermediate the reel andthe object carrying the free otherwise lost from the flasks as theytraverse end of the hose so as to rewind the conduit upon the reel. Thisconstruction becomes advantageous in connection with the moldingapparatus of my invention in that the slack is kept out of the flexibleconduit as the header fitting l9 moves from the major axis of the ovalconveyor path to the minor axis thereof. The rewinding characteristicsof the reel structure such as shown in Ludwig and Lea become unimportantwhere the conveyor path is circular or where other means are employed tocontrol the flexible, conduit.

A spring pressed valve 2i is interposed between the air conduit H orfluid pressure inlet chamber Ila and while the carriage unit l2traverses the jarring track section 30 a member 24 is brought intoengagement with the valve 2| so as to admit air or fluid pressure to theconduit l4 and thus raise the pattern table l3: As the carriage unitstraverse the anvil track 30 and the bar 24 the pattern plate i3 israised and lowered and following this station the conveyor units arebrought beneath a bar 31 which functions to scrape off the sand whichextends above the edge of the flask f. In this connection attention isdirected to the-pins i3 carried by the pattern table l3 which extendinto apertures I carried by the flask f and serve to retain the flask inposition on the table throughout the filling, jarring, scraping, andtamping operations (Figure 3). The station where the scraping takesplace. is indicated at F in Figure 1 and following the leveling orscraping action of the bar 31 the conveyor units pass beneath a tampingmechanism indicated at 38 which comprises a series of fluid actuatedrammers or tamping plungers 38a.- The plungers 38a continuouslyreciprocate and the enlarged heads thereon serve to uniformly tamp andpack the sand into the flask as the flasks continuously movetherebeneath.

Following the tamplng or packing station indicated in Figure 1 as at Gthe units pass beneath a leveling or strike-off device 39 which trowelsor smooths the sand flush with the top of the flasks. Preferably theupper edges of the flasks fv are sloped downwardly as at 39b tofacilitate the smooth troweling or ride-over movementof the device 39which is. mounted to permit a limited vertical movement. After leavingthe" flnal level-- ing or sand packing device 39 the units come to avibrating station indicated in Figure 1 at I and defined by the bar 23in Figure 2. As'the continuously raised and through rods i2i con-'nected therewith will move the flask I away from the pattern p in themanner illustrated in Figure- 3; The bar 26 having considerable extentalong the conveyor path maintains the flasks in their raised positionwhile they approach the .station'indicated at K at which station theyare areprovided with a continuous sand pit therebeneath and the sandwhich is jarred, scraped or veyor. end 43 which is adapted to engage thewheels 43c and raise the weights'flb clear of the flasks f. To ensure asmooth lowering action and consaid stations drops into the sand pit 33.The lower wall of the sand pit 33 is provided with a conveyor belt 36,the upper end of which travels in a direction opposite to the travel ofthe conveyor units and functions to return the sand dropped into the pitto the sand conditioning apparatus 6.

Any suitable means for driving the conveyor unitsor machines i2 may beemployed, for example, a continuous sprocket adapted to engage the axleshaft or the track wheels l2a could be provided and mounted at anyconvenient point adjacent the tracks 3|. Preferably the machines areconnected in tandem and their travel is continuous throughout the pathof the conveyor.

Referring now particularly to Figure 1, it will be noted that a mold orflask transfer conveyor generally indicated at 40 is mounted adjacentthe mold-making conveyor and is timed with the latter. A preferred typeof conveyor is shown in Figure 5 and comprises an overhead track 40ahaving suspended therefrom a series of bale hooks 40b through the,medium of hoist mechanism generally indicated at 400, the respectiveunits being connected by a flexible chain or like member as at 40d, thebale hooks 40b having a universal suspension connection with the hoistmechanism 400. The flasks are provided with trunnions 41, so that anattendant may stand adjacent the, point of transfer and engage the hooks40b over the trunnions 4|.

While the conveyor 40 is shown more or less in detail in Figure 5, itwill be understood that this showing is simply to illustrate anoperative mechanism and is not to be construed as alimitation on thecombination of apparatus as aparts are matched and the flasks closed, itis generally necessary that they be held in clamped or weighted relationto prevent separation or displacementduring the pouring operation andsubsequent cooling of the metal. In the present instance, this clampingoperation is performed automatically by means such as that illustratedmore or'less in detail in Figures 6 and 7 and shown-in plan at the rightof Figure 1. This mechanism comprises a series of weights 43 each ofwhich is carried by a support or holder 43a, the latter in turn beingadjustably secured to a trunnion bracket arm 43b in which a wheel 430 isjournaled. A stationary semi-circulan cam track 430' is installed at theone end of the conveyor 42, and the wheels 30 travel on these tracksduring the time the weights 43 are in in- .operative position. Apedestal bracket 43d is mounted on a conveyor 43c, and the bracket arm43b is pivotally connected to said. pedestal bracket. The conveyor 43eis continuous and may be operatively connected to, or driven insynchronism with the mold assembling and'pouring con- The track 430' isprovided with a cam tact of the weights 43b with the flasks f, ashockabsorblng or retarding member 44 is preferably provided, noteFigure .6, and may consist 01 a fluid cylinder having a plunger amounted therein to which an arm 44b is connected, the latter in turnhaving a sliding pivotal connection with the arm 43b. The cylinder 44 isconnected to the pedestal bracket 43d and may be provided with the usualby-pass ports common to devices of this type.

The flask weights 43 above described obviate the need for moldclampingdevices and this renders my system more nearly automatic and bettersuited to high speed production. The need for mold weights, that is,weights to hold the sand in the flask compact during the pouring andsetting period is obviated by the use of flask bars ,b as indicated inFigure 2. The strain put upon the mold while the metal is being pouredtherein is taken by the transverse flask bars Ib and since the massiveflask weights 43 which I have provided eliminate the need forconventional mold clamp pins the foundry worker's time is not consumedfastening and unfastening a plurality of clamps or latches.

The operation of this mold clamping or weighting assembly is follows:

The track 430' constitutes part of a circle or the said track isdiscontinued adjacent the poursection 1: of the conveyor 32, so thatwhen the units 43 reach a point in registration with the travelingflasks, they drop off of the end of said track and lower onto the top ofthe flasks.

During this time, the pouring operation is completed, the weightsremaining on the flasks until the latter reach the cam end 43f,whereupon the weights are raised clear of the flasks.

The conveyor 42 extends to a point adjacent sand shake-out mechanismgenerally indicated at 45, and which mechanism is more or lessdiagrammatically illustrated since it may be of the conventional typeobtainable in the open market.

The sand from the molds falls through a grating 46 and onto a returnconveyor 41 which conveys the sand back to the conditioning plant 5.

Adjacent the shake-out mechanism and above the conveyor 41 is a gravityflask conveyor 48 which returns the empty flasks to a flask returnconveyor 49, the latter being of substantially the same type as theconveyor 40 and operating in substantially the same manner.

The operation of the machine may, of course, be varied to suitconditions, but in general is as follows:

At A, one or more attendants clean the patterns and set chaplets; at B,an attendant places the drag flasks on the pattern plates; at C, thecope flask is placed on the pattern plates; the foregoing operationsbeing manual and capable of being performed by unskilled labor.

At D, sand is directed into the conveyor through the hoppers 9, 8a or92), the sand as it drops through the hopper or hoppers being subjectedto the aerator l 5.

At E, the machines l2 pass the cam 24 (note Figure 2) and the valve 2iis depressed and air admitted to the jolt cylinder l2c, whereupon thejolting operation takes place automatically.

At F, the device 3'5 serves to rough plow or strike on" the surplussand, after which the flasks pass beneath the rammer 38, this oper ationtaking place at station G.

At H, the sand is leveled substantially flush with the top of the flaskby the device 39.

At I, the cam 25 contacts the valve 22 and opens the line to thevibrator cylinder; and approximately at J, the stripper valve 23 isopened flasks being held in elevated position along the station K togive time for one or more attendants to transfer the molds to theconveyor Ml, the attendants simply engaging the bale hooks 40b over thetrunnions 4| of the flasks, the actual transfer operation taking placeabout at L.

At M and M, the molds are matched and closed, or in the case of a corejob, the core may be Isgt at M and the molds matched and closed a Thepouring station is indicated at N, and just before reaching thisstation, the weights t3 are lowered onto the flask due to the fact thatthe wheels 43 have moved clear of the raised track 430'.

That section of the conveyor between the pouring station N and thestation may be considered as the cooling section; and when the moldsreach the station 0, an attendant transfers the flasks to the shake-outmechanism, from which point they are placed on the conveyor 38 andpassed down to station P, where they are placed on the flask-returnconveyor and re- "tilrned to the stations B and C, where they are placedover the pattern plates and the cycle repeated.

The patterns which are exposed at the left hand extremity of Figures 1and 2 illustrate how varying types of castings may be made continuouslyand without interruption regardless of their size, shape or weight. Inother words, a mixed job may be run as easily as a single or similarline of castings.

In Figure 8, a modified type of mold-making mechanism is shown which isparticularly adapted for relatively small work where the parts to behandled manually are not overly heavy. In this instance, the flasks maybe stripped manually. The conveying track is indicated at 56, theconveying machines at and the flasks at f. The machines 5! arepreferably each provided with a depending bracket 52 carrying a bearingwheel 53 adapted to engage jarring cam members 5 3 formed on an anviltrack 5%, thereby performing the jarring operation automatically. Theinstallation in thisinstance is much simplified with respect to thatshown in Figures 2 and 3. It will be obvious that certain of theapparatus shown in Figures 2 and 3 may be utilized in this modifledstructure, notably the gravity feed of the sand. This combination, or agravity feed with a mechanical jarring action, results in a muchsimplified arrangement; and in the case of certain types of shallow orlight work, the jarring mechanism may be entirely dispensed with.

-It will be understood that certain changes in structure and design maybe adopted within the scope of the invention as defined by the appendedclaims.

I claim: A

i. In a molding apparatus, a sand conditioning unit, a chute fordischarging sand into a flask, means for constantly moving a series offlasks beneath said chute, a constantly moving conveyor interposedbetween said conditioning unit and said chute to transfer sand from saidunit'to said chute, means within said chute to break up the lumps andballs of sand occasioned by movement along said conveyor and throw theagitated and aerated sand downwardly through said chute and directlyagainst patterns in the molding flasks disposed therebeneath.

2. In a molding apparatus, a sand conditioning unit, a chute fordischarging sand into a and the flasks raised clear of the patterns, theflask, a conveyor interposed between said conditioning unit and saidchute to transfer and discharge sand into said chute, means within saidchute to break up the lumps of sand occasioned by movement along saidconveyor and throw the agitated and aerated sand downwardly through saidchute and into the molding flasks disposed therein, said meanscomprising a shaft transversely arranged with respect to said chuteprovided with inclined blades and a motor to rotate said shaft.

3. In a molding apparatus having a series of interconnecting units.constantly traveling about a conveyor path, means to jar said unitsduring a part of their travel comprising a fluid pressure cylindercarried by each of said units, a plunger therein operatively connectedto a pattern and flask supporting table, means to admit fluid pressureto said cylinder comprising a flexible conduit leading from a fluidpressure supply to said units, a valve interposed between said flexibleconduit and said cylinder conduit, means adranged adjacent said conveyorpath and extending for a limited distance therealong to engage saidvalve to eiTect movement of the flask and pattern withrespect to saidunit.

4. In a molding apparatus, a series of interconnected mold unitsarranged to' travel about a closed conveyor path, said units comprisinga pattern table adapted to support a pattern and aflask, an air cylindermounted on said unit beneath said pattern table, a piston therein andmeans operatively connected to said piston and said flask to effect araising of said flask with respect to' said pattern table upon movementof the piston within the cylinder, a fluid pressure conduit leading fromsaid cylinder to a valve mounted onsaid unit, a member fixed withrespect to said conveyor adjacent the path thereof arranged to engagesaid valve means upon travel of said unit therealong, a flexible conduitconnected to said valve means and leading therefrom to an air-supplywhereby upon travel of said units about said conveyor path said valve isopened by'said member to admit air into said cylinder and the flask israised with respect to said pattern and pattern table.

5. In a molding apparatus, a mold assembly and pouring conveyorcomprising a series of interconnected flask supports arranged to becontinuously moved about a closed conveyor path, complementary flasksarranged upon said supports, a pouring station along said conveyor path,a mold flask clamping device arranged'at said pouring station comprisinga wheel having a series of weights pivotally mountedthereon andlaterally projecting therefrom, said wheel timed to rotate insynchronism with said flask supports as said flask supports traversesaid pouring station, means to raise said weights above the level of theflasks carried by said flask supports as they leave said pouring stationand means to lower said weights upon said flasks to effect a clampingthereof at said pouring station.

6. In a molding apparatus, a conveyor comprising a series ofinterconnected flask supporting units, said conveyor having one portionof its path curved to provide a pouring station, a flask clampingmechanism arranged at said portion of said conveyor path comprising awheel having a plurality of pivoted weights projecting laterally fromthe periphery thereof, the projection of said weights beyond theperiphery of the wheel being suflicientto overhang molding flaskscarried by said supports,-means toraise said weights above the plane ofthe top of the molding flasks as said flasks and weights leave saidpouring station and g I means to lower said weights and eifectivelyclamp said flasks during the pouring thereof.

.7. In a mold assembly and pouring system, a conveyor having anelongated path with curved ends, a series of interconnected flasksupporting units on said conveyor, a flask clamping wheel mounted at oneend of said conveyor path, said wheel having an axis corresponding tothe axis of the curved end of the conveyor path, a plurality of weightspivotally mounted on said wheel, said weights arranged to project beyondthe periphery of said wheel and overhang the flask supporting units ofsaid conveyor path throughout the curved end thereof, said wheel andsaid conveyor traveling in timed relation whereby each of said weightsoverhangs a complementary pair of flasks carried by said flasksupporting units, means to maintain said weights in a raised position asthe weights and flask approach each other, means to lower said weightswhen they have attained an overhanging relation with respect to saidflasks to efiectively clamp said flasks and facilitate thepouring'thereof, means to raisesaid weights with respect to the flaskssubsequent to said pouring said wheel and the curved portion of theconveyor path to a cooling section.

8. In a molding apparatus, a sand conducting unit, a chute fordischarging sand into a flask, a constantly moving conveyor interposedbetween therebeneath.

HENRY A.

whereby the flasks are free to move away from 'said conditioning unitand said chute to transfer

